Many beverages like espresso and other coffee beverages, milk beverages, chocolate beverages are prepared by mixing a food soluble powder with a diluent. Mixing devices are known for speedier preparation of such beverages by mixing the soluble food component with the diluent, such as water. These devices typically comprise a dissolution chamber in which the soluble component and the diluent are fed. The diluent can be introduced into the dissolution chamber in order to create a whirlpool to efficiently dissolve the soluble component in the hot water or the hot diluent can be introduced under the form of jets that provides mixing, dissolving and frothing. The mixture can also eventually be frothed by a whipper in the dissolution chamber to reconstitute the beverage and produce foam. The beverage is then usually evacuated into a receptacle for drinking.
The food soluble powder is usually stored in a container placed above the dissolution chamber opened mouth and a dosing device like a screw or an auger doses and delivers the food soluble powder which falls in the dissolution chamber. The dose is guided to the dissolution chamber opening by a chute that is attached to the container outlet or to the top of the dissolution chamber. Liquid is simultaneously fed to the dissolution chamber so that dissolution occurs. Several issues exist with such a configuration.
First the soluble powder frequently comprises fine particles which can easily flies when powder falls from the container through the chute to the dissolution chamber (volcano effect). These particles dirty the internal housing of the dispenser.
Secondly, due to the fact that the guiding chute emerges above the dissolution chamber then vapour and humidity generated during the beverage preparation in the dissolution chamber raises and enters the chute. If another beverage is rapidly prepared after another one then the new dose of powder delivered by the chute reacts partially with the humidity in the chute and creates non hygienic deposits in the chute. Vapour and humidity can even rise up to the outlet of the powder container and moisten its outlet or the outlet of the dosing device. After a period of time, this process can lead to an accumulation of moisture on the discharge port. As the quantity of soluble powder accumulating on discharge port increases over time, the outlet and/or the chute become increasingly constricted. Ultimately, this can result in the outlet becoming completely clogged, which results in the complete failure of the dosing device. Additionally, the soluble powder adhering to the discharge port is constantly moistened by the rising vapours. This can result in the soluble powder caking and even turning mouldy or growing harmful bacteria after extended use. This may lead to the dosing device rendering the powder ingredient inconsumable. This problem is generally solved by blowing or sucking air at the chute to deviate vapours as described in the following publications.
EP 2 085 002 proposes to close the top of the dissolution chamber with a cover during the beverage preparation and sucks vapour with a fan.
U.S. Pat. No. 4,245,680 proposes to blow hot air in the area of the powder delivery structure in order to create a warm air shroud which protects the structure from moisture.
U.S. Pat. No. 4,458,829 prevents the incursion of moisture into storage containers and prevent caking or hardening of the powders due to moisture absorption by having warm air circulation.
U.S. Pat. No. 5,839,610 describes the sucking of moisture and ingredient laden air from the top of the mixing bowl by an air fan.
U.S. Pat. No. 7,398,725 describes the use of an air current that transports the ingredient dose and prevents the rising steam from reaching the dosing device.
Current dispensers usually implement an extraction duct connected to a ring cap positioned at the top of the dissolution chamber as illustrated in U.S. Pat. No. 5,918,768. A fan sucks air from the end of the extraction duct.
Yet it has been observed that the proposed solutions are not sufficient and that current dispensers do still present cleaning issues and the internal parts of the dispenser must be regularly cleaned. In particular it has been noticed that powder fines systematically escape inside the machine housing. Due the presence of these fines the internal parts of the dispenser rapidly look dusty and dirty. The cleaning of these fines is difficult because they can be present in innermost recess and it is difficult to eliminate them.
Cleaning is a time consuming task because the dissolution chamber and the chute must be dismantled, cleaned and then reassembled. Moreover the cleaning must be done by people that have been trained for the disassembling and the reassembling to avoid errors and further failure in the beverages production. Usually this cleaning is made by an operator dedicated to the maintenance of the beverages production machines. Now there is need for decreasing the time for the cleaning operation to limit the period of time during which the dispenser is not operable. Moreover as people operating the dispensers are less and less trained there is a need for a dispenser that does not have to been cleaned on a daily basis.
In order to avoid that powder fines enter inside hydraulic and electric devices the housing of beverage dispenser has been split between a back proper area for these devices and a front less proper area by means of a separation wall. But this solution does not solve the problem of dirtiness in the front area.
An object of the invention is to address at least some of the drawbacks of the prior art beverage dispensers or at least to provide an alternative thereto.
It would be advantageous to provide a beverage dispenser that does not get dirty rapidly.
It would be advantageous to provide a beverage dispenser in which the frequency of manual cleaning operation can be reduced.
It would be advantageous to provide a beverage dispenser in which the extraction of humidity generated during beverage preparation is optimally controlled.